Entrainment and chaos in a respiratory neural network model with oscillatory input

Abstract

We study the dynamical behavior of a respiratory central pattern generator (CPG) model under oscillatory inputs. To characterize the physiological role of oscillatory input in a realistic CPG system, we chose a model with a minimal number of respiratory neurons which generates a stable oscillation for oscillatory or constant input. We simulated the system using sinusoidal waves with various amplitudes, frequencies, and relative phases. We also studied the critical number of inputs for entrainment to occur. The results suggested that for normal physiological oscillations, inspiratory and expiratory neurons should receive anti-phase oscillatory input. We also found various oscillation patterns including chaotic oscillations induced by the CPG under in-phase oscillatory input to the inspiratory and expiratory neurons.